JP3210125B2 - Ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly, to a joining structure of an ink flow path plate and a substrate having pressure generating means for generating pressure in an ink flow path of the ink flow path plate. In particular, it relates to an airtight seal structure.

[0002]

2. Description of the Related Art FIG. 6 is a cross-sectional view of a main part of an ink jet head as an example to which the present invention is applied.
0 is an ink channel plate having a plurality of ink channel grooves 11,
Reference numeral 20 denotes a position 21 corresponding to each of the ink flow grooves 11.
A substrate having a pressure generating means,
0 and the substrate 20 are joined by aligning the ink flow path 11 and the pressure generating means 21 with each other.
Is formed as an ink flow path.

[0003] The example shown in FIG.
In this case, a piezoelectric element is used.
Are provided with a plurality of parallel slits (concave portions) 22, and convex portions 21 and 23 are formed on both sides thereof. The convex portion 21 is a driving portion, and 23 is a non-driving portion. The non-driving portion 23 is joined to the convex portion 12 of the ink flow path plate 10, thereby forming an ink flow path. In the illustrated example, a piezoelectric element is used as the pressure generating means. Therefore, in order to prevent insulation of the piezoelectric element from being reduced, the ink flow path plate 10 is used.
And the pressure generating substrate 20 are connected with the adhesive 40 through the thin plate 30.
However, for example, in a bubble ink jet head using a heater as the pressure generating means, the ink flow path plate and the pressure generating substrate may be directly bonded without using such a thin plate. .

[0004]

In the ink jet head as described above, the connection between the ink flow path plate and the pressure generating substrate is further ensured, and the independence of individual flow paths (prevention of crosstalk) is ensured. It is necessary to increase the rigidity (increase the Young's modulus and improve the elasticity) and effectively increase the internal pressure of the ink in the flow path. Therefore, an object of the present invention is to complete the independence of the individual ink flow paths and improve the rigidity in the ink flow paths.

[0005]

In order to solve the above-mentioned problems, the present invention provides: (1) a flow path plate having a plurality of ink flow path grooves; and a pressure generating means provided corresponding to the ink flow paths. A plurality of ink flow paths formed by joining the flow path plate and the substrate with the ink flow path grooves and the pressure generation means facing each other, and driving the pressure generation means. In the ink jet recording apparatus for performing recording by ejecting ink jet from the ink flow path, a connecting portion of the flow path plate with the substrate extends parallel to the ink flow path and faces the same.
And a projection which is linearly in contact with the substrate, and (2) the extension of the projection .
That in the cross-sectional shape perpendicular to the direction, it <br/> tip shape in contact with the substrate is a triangular-shaped or hemispherical, or,
(3) a metal film, an organic film having a high hardness, or an inorganic film, or a multilayer film obtained by combining them on the surface of the projection; or (4) a surface of the substrate to be joined to the projection. Having a thin film, alloying, fusing, or diffusing the material of the thin film to improve the bonding strength, further,
(5) The flow path plate and the substrate are pressed and held by a heat- shrinkable film / resin.

[0006]

A projection is provided in parallel with the ink flow path of the ink flow path substrate, and the ink flow path substrate is pressure-bonded to the ink pressurizing substrate via the projection to improve crosstalk between the ink flow paths.
Further, the rigidity in the ink flow path is increased to effectively pressurize the ink in the ink flow path.

[0007]

FIG. 1 is a sectional view of a main part for explaining an embodiment of an ink jet head to which the present invention is applied.
FIG. 1 shows an example of an ink jet head using a piezoelectric element as an ink pressurizing unit. In the figure, parts having the same functions as those of the prior art shown in FIG. Is attached.

Thus, in the present invention, the joint of the ink flow path plate 10 with the pressure generating substrate 20 (in the illustrated example, the thin plate 30) is not a flat surface (see the joint surface 12 in FIG. 6).
As shown in FIG. 1 (a), it is preferably formed in a projecting shape 12a, and preferably, as shown in FIG.
Are pressed and joined so as to fit into the joint of the pressure generating substrate 20 (the thin plate 30 in the figure).

[0009] the protruding portion 12a, as shown in FIG. 2, triangular-shaped (preferably, an acute angle) 12a, or, by the hemispherical 12b, to enhance the airtightness between the adjacent ink passages The sharp projections 12a increase the depth of engagement with the facing bonding material, and the hemispheric projections 12b increase the contact surface by making the contact points linear. In both cases, the partition is completely divided, and separates the vibrator and the ink chamber. This is a thin film 30 (aramid, capron / P
PS film, PES, etc.).

FIGS. 1 and 2 show an example in which fine projections 12a and 12b are formed on a part of the joint plane, but when it is difficult to form fine projections, for example, ink When the flow path size is as fine as 200 dpi to 800 dpi, as shown in FIG. 3, relatively large projections 12c and 12d using the entire joint are formed.

FIG. 4 shows that a film 5 having a thickness of about 1000 ° to 1 μm is formed on the surface including the triangular or hemispherical projection-shaped structure.
In the drawing when film No. 0 is formed, this film 50 has resistance to ink, prevention of humidity swelling, improvement of rigidity, corrosion resistance, improvement of ink wetting, prevention of generation of bubbles due to gas permeation, improvement of adhesive adhesion, pressure bonding It is provided to prevent deformation of the tip of the projection when biting in. In particular, acrylic and polycarbonate resins have high moisture permeability and gas diffusion coefficient, which are disadvantages for ink jet nozzles. It can be compensated by selecting the material.
Depending on the purpose, the characteristics can be improved by forming a multilayer film, and further, the adhesive strength between the plastic molded product and a metal or an inorganic material can be improved.

As the thin film 30 for separating the ink chamber and the vibration element, a material having rigidity and ink resistance such as imide type, amide type, PPS, PES, etc. is selected. A film 60 having a thickness of about 1000 to 1 μm is further formed on the film 30 having a thickness of about 5 to 10 μm for the purpose of improvement, prevention of moisture permeability, prevention of air permeability, and improvement of a bonding force at the time of bonding.
Thus, when a film having high rigidity is used as the film 60, the effect of pressing the piezoelectric element is dramatically improved. Surface material 5 of protrusion
When the material of the film 0 and the material of the film 60 are the same, adhesion by heat diffusion and fusion is possible, and microwave is used for heat, but an oven may be used in some cases. Also, the bonding of Si-Au
It is fixed at 150 to 200 ° C. under pressure and heat. In addition, even in the case of ultrasonic fusion, local heat is generated, and adhesion of the film is improved. Further, in the case of a metal film, the energization causes heat generation and substance diffusion on the contact surface, and the adhesion is improved by energization fusion.

FIG. 5 is a diagram showing an embodiment in which the ink flow path plate 10 and the substrate 20 are pressure-fixed as described above, and this fixing is made firm and the fixing is maintained. in, the embodiment shown in FIG. 5 (a), heat-shrinkable film 90
Example shown in Fig. 5 (b) is a stainless steel plate
An example in which the resin 90 is pressed through the reinforcing plate 80 of FIG.
Show .

As described above, in the present invention, the separation of the individual flow paths is completed by linearly joining the separation of the partition walls of the individual flow paths to the contact surface of the opposing component and pressing and fixing them. . This depends on the pressing force because of the linear joining. However, when the material is polysulfone with a flow channel plate of 64 channel nozzle (length: 12 mm) and a pressure of 10 kg is applied, the joining protruding structure has a leading end. Was deformed and crushed by about 10 μm. At this time, the bonding surface was fixed by pressing at about 120 kg / cm ² , and the surface of the opposing bonding member was partially intruded. There is no ink flow between adjacent walls of the road and no crosstalk is observed.

With respect to the rigidity, a material such as polysulfone, which is a hard material mixed with a filler such as glass fiber or SiO _2, can be fixed by pressure while maintaining its rigidity. Even if the rigidity is a little small such as acrylic or polycarbonate, Ni, Mo, T
By forming a metal film of i, W, Ru or the like on the order of 1000 to 1 μm, the rigidity in the ink flow path can be improved. As the organic film, a diamond film, a parylene, or a surface coat of an imide-based resin has improved rigidity. SiO ₂ , SiON, SiN, BN, Ti
It is possible to form a film having high rigidity such as N, AlN, Al ₂ O ₃ , TiO _{2 and the} like.

Further, the surface of the metal film is subjected to oxygen plasma treatment or an oxide film is formed on the surface layer by reflecting the film with O ₂ at the time of film formation, thereby improving the rigidity and improving the reliability with respect to ink and humidity. It is also possible, for example, to form a film with Al and coat the surface with Al ₂ O ₃ .

In addition, it is necessary to improve the adhesive strength after pressure fixing. In such a case, by matching the surface coating material and the surface material of the facing joint component, the surface can be humidified, ultrasonically or energized. By fusing and diffusing the material, the adhesive strength can be dramatically improved. Further, in the case of joining between resins, it can be improved by fusion bonding by ultrasonic wave, microwave heating or the like. In particular, when a material having high rigidity is formed when the rigidity of the flow path plate material or the film separating the ink chamber and the piezoelectric element is low, the surface of the ink chamber is formed of a material having high rigidity. The effect of reducing the amount of the transmitted vibration to be absorbed by the inner wall of the ink chamber and increasing the ink ejection output is exhibited. Oxidation of the film-forming material improves ink resistance, and of course increases the rigidity of the inorganic oxide, thereby improving reliability and improving the characteristics of the ink jet nozzle. The material of the protruding structure made of a single plastic is fused by applying ultrasonic waves in a temperature atmosphere near the TG of the material. Also, fusion can be performed by using both microwave heating and ultrasonic waves (combined use). In particular, the dissimilar plastic can be fixed by pressure welding.

[0018]

As is apparent from the above description, according to the present invention, since the flow of ink between the ink flow paths can be reliably prevented, there is provided an ink jet recording apparatus having high recording accuracy without crosstalk. can do. Further, since the rigidity in the ink flow path is increased, there is an advantage that the pressure of the ink in the ink flow path can be effectively increased.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram for explaining an embodiment of an ink jet head according to the present invention.

FIG. 2 is a main part configuration diagram for explaining another embodiment of the ink jet head according to the present invention.

FIG. 3 is a main part configuration diagram for explaining another embodiment of the ink jet head according to the present invention.

FIG. 4 is a main part configuration diagram for explaining another embodiment of the ink jet head according to the present invention.

FIG. 5 is a main part configuration diagram for explaining another embodiment of the ink jet head according to the present invention.

FIG. 6 is a main part configuration diagram for explaining an example of a conventional ink jet head.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Channel plate, 20 ... Pressure generating board, 11 ... Ink channel groove, 12a, 12b, 12c, 12d ... Projection part, 21 ...
Driving part convex part, 22 ... concave part, 23 ... non-driving part convex part, 30 ...
Thin plate, 40: adhesive, 50, 60: membrane, 70: leaf spring,
80: reinforcing plate, 90: heat shrinkable film resin.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-8388 (JP, A) JP-A-3-262645 (JP, A) JP-A-55-82664 (JP, A) 101955 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 2/045 B41J 2/055

Claims (5)

(57) [Claims] A flow path plate having a plurality of ink flow grooves;
A substrate having a pressure generating means provided corresponding to the ink flow path, and joining the flow path plate and the substrate with the ink flow path groove and the pressure generating means facing each other to form a plurality of inks. In an ink jet recording apparatus which forms a flow path and drives the pressure generating means to eject ink jet from the ink flow path to perform recording, a joining portion of the flow path plate with the substrate is parallel to the ink flow path. Before extending and facing
An ink jet recording apparatus comprising a projection linearly contacting the substrate . 2. The projection is orthogonal to the extending direction.
In cross section, the ink jet recording apparatus according to claim 1, the distal end portion shape in contact with the substrate characterized in that it is a triangular-shaped or hemispherical. 3. The inkjet according to claim 1, wherein the protrusion has a metal film, an organic film having a high hardness, an inorganic film, or a multilayer film formed by combining them. Recording device. 4. The substrate according to claim 1, wherein a thin film is provided on a surface of said substrate which is to be joined to said projection, and a material of said thin film is alloyed, fused or diffused to improve a joining strength. 3. The inkjet recording apparatus according to any one of 3. 5. A heat- shrinkable film comprising:
5. A pressure holding device made of resin.
The inkjet recording device according to any one of the above.